Gearing



Ju e 13, 1944. F. E. 'MBMULLEN 2,351,219

' 'GEARING.

Filed March 13, 1945 4 Sheets Sheet 1 ZSnventor FREDER/gk E. M; 'MULLE/V June 13, 1944. F. E.'McMULLEN GEARING' Filed I March 15, 1943 '4 Sheets-Sheet 2 Bnncnto.

FREDERICK E. MC MULLEN filming June 13, 1944. F.E. M MULLEN 2,351,219

GEARING V Filed March 13, 194; T4 Sheets-Sheet 5 Buncntor FEEDER/CK E. M: MULL EN v j flttorneg June 13, 1944. v FQ 'MGMULLEN 2,351,219

GEARING Filed March 13, 1943 14 Sh'eeis-Sheet 4 FREDERICK 5. Mc MuL'Ls/v attorney Smaentor I Patented June 13, 1944 UNITED STATE-S PATENT OFFICE i GEARING-Q. f Frederick McMullen, Rochester, N. Y., assignor to Gleason Works, Rochester, N. Y., a corporationof New York Application ath is, 1943, Serial No. 479,011

e cranes; (QIQ'MQ-ZSZ) The present invention relates to powered gear drives and particularly togear drives :of the type employed inthepropulsion ofshipsu I For many types of ship drives, the geared steam turbine has advantages over the old-style, recip rocating steam engine or the turbine electric drive. For a given horsepower output-,the geared steam turbine is lighter in weight-andoccupies less space. Moreover, it consumes less steam, and consequently less fuel, andreq-uires less fuel storage capacity and a smaller boilers -With;a-geared steam turbine, then, it is possible to either'save space for carrying extracargo, or to' use the space, which might otherwise be saved, for a larger size steam turbine, and increase the speed of the vessel, so that over a period of time it can transport a. greater amount of cargo.-.j 1

It has beenthepractice heretofore to use herringbone or double helical gears ingeared steam turbine drives. The customary drive-consists of a double herringbone reduction with the last reduction gear, or so-called-bull gear,of'ex-. tremely large size. Herringbonei gears :ofilarge sizes takea long time to cut anywayibecause they have to be hobbed. In' addition to this, how ever, it is difficult to harden them evenby the flame hardening process, and consequently they usually have to be madefrom very hard steels, which do not require'tobe'hardened' afterthe teeth have been cut; The hard material creases thecutting time required, and itusually takes many days even weeks to-cut a s'ingle'herringbone bull gear forfa ship 'propulsion'unit.

The manufacture ofzthis gear is 'one of the bottle-necks in shi-p production? ,lBecause'of the'difliculty of manufacturing: these: gears in the quantity required ,forllwar. time needs,'-it-hasbeen necessary. to usereciprocating steam'engines and'electric turbines in most cases for=ship.pro.-, pulsion instead. of the more desirable-geared steam turbine. 1 l

One object of the present invention is tolpro vide a drive suitable for a'geared steam turbine propulsion unit, in which much smallersize'gea'rs may be used than: .thoseheretofore. required. Such gears can be produced faster. and in.z-the quantities required 'fo'rl-waretime' shipping re,-

quirements'. J v. 1 U 1 A further object of "the invention istoprovid a geared steam turbine drive in which a herring bone gear may still be used as the bull?! gear but in which the sizeof this gear may be reduced considerably as compared" with previous: herringft. ,A

" a-drive, suitable for a geared steam turbine pr0;

pulsion unit, from which herringbone and helical; gears can be eliminated'entirely, and in which bevel gears can be used instead.

. Still another object of the invention is to .pro--.

vide a reduction drive in which part of the gear-l v propeller shaitrjT-he other side gear -of-each i Another object ofj the invention lis -to ingof the drivemay be used not only for ,a reduction but also as a bearing for supportingthe,

bull gear, thereby eliminating the c0st-0f the huge anti-friction bearings usually'- ,required for this purpose; and, moreover, conserving space. Otherobjects of the invention aretof pr ovide a drive, suitable for a geared steam turbine. propulsion unit, which will be more compact, require less'space, and be easier to produce thandrives heretofore used. I Still other objects of theinventionwill appear, hereinafter from the specification and from the, recital of the appended claims. T 3 In the driveof thepresent invention, three reductions are used,=bu t one of these reductionsis a set of planetary gears. This'zconstruction. permits of using relatively small gearsin all of. the reductions of the unitand, moreover,;makes it possible to keep the unit quite compacti Preferably, the planetaryis-a bevel gear planetary, and preferably one side gear of theplanetary; is connected to the driven member of the second reduction, that is, the fbullf gearp -Thespider,

The planetary provides a two to one reduction,-

and the further reduction required between turbines and;the propeller is attained.by suitable selection of the ratios of the first and second re ductionsof the unit. The first and second re-s H. ductions may beherringboneqgearsbut bevels are preferably used for these;reductions-also: Bevel gears can be cut inmuch less time ,than herringbone, can easily be hardened by theyfiame'; hardening process, and "can readily, be lapped and ground. so ;that extreme. accuracyand ex-;

tremeaquietness in the drive cambeobtained,v

. In one embodiment of the inventiomthere are two planetary gear units emp1oyed,-. one-mount ed ,atw'either side of the second reduction gear; One side gear of each planetary is thenconnectedz tothe second reduction gear, while one ;0r;bj0.th of the planetary spiders are connected: 1305121113" planetary-is fixed ,to 'the reductionwhousing. These latter side :gears act then,- as bearingsitjto carry the planetaries, the bull gear and the propeller shaft. The planetaries are coaxial with the "bull gear, and the whole makes a very compact unit. 7 7

Several different embodiments of the invention are illustrated in the accompanying drawings, in which:

Fig. 1 is.a developed sectional view of a, drive made according to one embodiment of this invention;

Fig. 2 is a view of the reduction unit of Fig. 1 in place in its housing, part of the housing and bull gear being broken away to show the second reduction pinions and, in.section,-the spider of the planetary, which is used for thethird reduction;

Fig. 3 is a developed sectional view of a further embodiment of the invention, showing 'a drive in which two planetary units are incorporated and serve not only as a, third reduction but as bearings for the bull gear orthe second reduction and'for one end of the'prope'ller'shaft; and

Fig. 4 is a sectional view of a' still further embodiment of the invention, in which herringbone ears are used 'for the second reduction while'two sets of bevel planetaries are used for the third reduction and forsupporting the driven member of thesecond reduction and one end of the- 'propeller shaft.

Referring first to the embodiment of the inventionillustrated in Figs. 1 and. 2, I and II denote,'respec'tively, the prime mover shafts of the propulsion "unit. These shafts are connected in any suitable manner to low'pressure and high pressure steam turbines, respectively. The shaft I0 is journaled on suitable bearings I2 and'I3 in asupport I4. The-shaft II is'journaled (insult,- able b'earings I6 and 'I'I in a support I8.

I The shaft'IIl carries a "bevel pinion 2| at its inner endwhich meshes with a bevel gear 22 that is keyed "or otherwise secured to'a sleeve'23. The sleeve 2'3 isformed with a toothed face clutch member'24 at one end which engages with a toothed face clutch member 25 that is keyed-or otherwise secured to a shaft 26. The sleeve *23 and shaftj26 are journaled in the casing 15 (Fig. "2) on suitable bearings 21, 28, 2'9 and '30.

The-shaft I-l carriesa bevel pinion at its'inner end which meshes with a bevel gear '36 that is keyed or otherwise secured to a's1eeve31. This sleeve 31 is provided with a clutch member "38' at its outer end which engages with a clutch member 39 that is keyed or otherwise secured to a shaft 40. Sleeve 31 and shaft 40 are journaled 'inthecasing 20 on suitable bearings II, 42, 43,an-d44. r

There is l a spiral bevel pinion integral with the shaft '26, and there is'a spiral bevel pinion'BI integral with the shaft -40. These pinions rnes'h with a spiralbevel ring gear 52. "This ring ear is secured to a'rabricated hub member lid'whichis rotatably mounted by means of suitablebear'in'gs and 56 ua-shaft 51.

the side gear 62 is bolted or otherwise secured to the housing I0 for the gear unit. The casings l5 and 2|] are fixedly mounted on'this housing Ill. The shaft'5I is coupled to the propeller shaft II of the ship by a toothed face clutch, one member I2 of which is keyed to the shaft 51 and the other member I3 of which is keyed to propeller. shaft II.

"The ratios of .the bevel gear'reductions 2I-22 and 35-36, respectively, are determined by the r P. M. of the low pressure and high pressure turbines, respectively, which actuate the drive,

' and are so selected that the shafts 26 and 4G rotateat-the .same speed. The planetary unit withthe planetary unit 60, BI, 62 to give the desired R. P. M. on the propeller shaft of the ship. 'Byusing the planetary gears, thesizeof the' 'gear 52 -can'be kept small as compared with the size of the bull gears used in'convent'ional drives. Moreover, the-drive is kept compact be cause the drive gear 60 of theplanetary unitis connected'direcflytothe'driven gear 52 of the second reduction. v 4

7 *In-"the embodiment of 'the invention illustrated in Fig.8; :the two shafts, which'are connected to the low pressure and high pressure turbines, are denoted' at'llll and 8I,-respec'tively. The shaftBfl isjou-maled in' the housing 62 on'bearings 83 and 64. The shaft "8' Iis-journa1e'din the housing 62 'on bearings 85 and '86.' The shaft 80 is formed at its inner end with a bevelpinion 88 which meshes with a bevel gear 8'9. This gear is keyed or otherwise fastenedto a sleeve 9Ilthat is provi'ded w ith a toothed face clutch; member El at its outeriend. "The clutch member 9'I engages with a' 'ellitch memberfll that is keyed or otherwise secured 'to-the shaftf93. Thesleeve 9El-and the shafti63 -are journaled in-the housing 82,'bein'g mounted onsuitablebearings 94, 95, 96, and 91; *Tne'sna'rtal has abevel' pinion IIIIJ formed at itsjinner end which meshes with a bevel gear I U I Thebevel gear iILllI is keyed-or otherwise secured to'Ja sleeve "I02. The sleeve 1-02 is formed at its outerendwitha faceclutch member I03 which I engages with a'face-clutch member Ill'fl'that is keyed or otherwise secured to a shaft I05. "The sleeve 102 and the-shaft 1 05 :are journaled in the housing .82 onlbearings I06, I 01, I08 and I09.

The'ishaft'fl has, afspiral bevel pinion III) integra l with: it,1and the-shaft I05 has a'spiral bevel pinion I-II integral with it[ These two pinions meshtwitha spiral bevel. ring gear H2. The ring eal'tllis bolted'or otherwise :secured to a'fabpinions are journaled on suitable' bear-ings and GS- in-a spider-"66. 'I'heyare secured'a'gamst'axial.

movement relative 'toithe spider by plates BI WI liCh are fastened-to thespider by screws 68. 'i

The-spider 66- is keyed to the shaft 51} while ricated'hub member 'I I4. JThe' hubmember 1H4 ha'sitwo bevel gears I I 5 and III; bolted or otherwise secured'to it. These'gears are coaxial with the ring gear II2 but are mounted .on the hub member H4 'at opposite *sides'of :the ring gear I*I2.' Theitwo gears vII-5 andHG are side gears QfTbWOiTbEVGl gear planetary reduction units.

"Thief-planetary unit'ofwhich'the gear H 5 is an element,'.:comprises in addition to gear IrI5, a set orloevelpinions illl'and the bevel sidegear I IS. The planetary unit of which the bevel gear :I I6 rs 2am ielenient, comprises-in addition to the gear IIIL'casset ofz'bevel pinions ljznr-anda bevel side.

in any suitable-mannerEtothehousing F82, Za'nd-a shim I28 of. suitable thickness may beainterposed adjusting. the gears of .the planetaries in proper engagement. The pinions II1 are journaled on suitable. bearings I 22.v andl23 ina spider I24. The pinions I are journaled. on suitable bearings: I25 and I26 in a-spider I21. The hub member H4 is journaledon the spiders I24 and I21, bushings I29 and. I30; being provided for this purpose. The. spider. I24is connected by a toothed faceclutch, which is (1611017861435 a-whole at I32, with the propeller shaft I33. This shaft is coaxial with the spiders I24 and I21- andwith hub member H4 and ring gear II2. One member of clutch; I32 is formed integral with the spider I24 and the other member is keyed to the shaft I33. A similar clutch may be. provided to connectthe other spider I21 with the shaft I33, but preferably the spider: I21 ismounted to rotate freely on the shaft I33- The drive to the shaft is :transmitted, then, solely through the spider I 24.; The axial thrusts on the shaft I33 are taken 5.

by thrust bearings I35 and I36, which are mounted at eitherside of aithrust plate I31 that is secured by a nut I38 against a shoulder formed on the shaft I33. A shim I28 of. suitable thickness may be interposed betweenstationary side-gear and the housing 82;.to permit adjusting the planetary gears. into proper mesh. 1

With' the construction shown in Fig. 3, it will be'seen. thatthe spiders I24 and I21 support the propeller shaft I33, .andthese spiders are in turn supported by the stationary side gear H8 and I2I. of thetwo planetaryunits, so that the two planetaries act,-therefore, as bearings'not only for thehub member I I4 and ring gear I I2, but also for the propeller-shaft itself. Thus, need for separate radial bearings and the space required for these bearingaaare eliminated. v i The advantages .ofthepresent invention are not. restricted to. reductions employing bevel gears. It may beusedi also in'drives employing other types of gears.'.-1hus, Fig- 4 shows a drive built according .t0?.thl's invention in which one reduction consists of herringbone gears and the other reduction of a bevel planetary.

In Fig. 4, the shafts I40 and MI correspond to the shafts 26 and 40, respectively, of the unit shown in Fig. .1, and to the shafts 93 and I05, re-

spectively, of the unit shown'in Fig. 3. The shafts I40 and MI, in'other words, are driven from the lowspeed and high speedturbines, respectively, through suitable reductions, 'not shown. The shaft I40 has a herringbone pinion I42formed:integral with it; and the shaft I4I has aherringbone pinion I43 formed integral with it. These tw'o'pinions mesh at spaced points with a herringbone bulPgear I 45 to drive' the-same.

There are two-bevel gears I46'and I41 secured in any suitable manner to-opposite sides, respectively, of the "herringbone gear I45 to rotate with the gear I45. These' two gears I46 and "I 41 are side gears, respectively,- of "two 'bevelplanetary units which are mounted at opposite sides of the herringbone gear I45. The planetary, of which the gear I46 is'one element, comprises the bevel side gear I46, a set of bevelpinions I48, and the bevel side gear I49. The planetary, of which the bevel side gear I41 is onefelement, comprises the bevel side gear I41, a set of bevel pinions I 50, and a bevel side gear I5I.

The side gear I49 is bolted or secured in any other suitable manner to a plate I52, and this plate is secured in any suitable manner to the housing I 53 of the reduction unit. The side gear i5I is bolted 0r otherwise'secured to a plate I55, and this plate is also secured to the housing I53.

lib

Theslde gears I49'and I.5I are, therefore, stationary. Shims I54 and I56 may be interposed between the plates I and I52, respectively, to permit of positioning the gears ofthe two planetaries in proper engagement.

The planetary pinions I48 are journaled on studs I59 that are integral with a spider I51, and they are held in position onthe studs by nuts I58. The spider I51 is keyed to the shaft I60. The planetary pinions I50 are journaled on studs I6I that are inte ral with a spider I62, and they are secured on the studs by nuts I63. The spider I62 is connected to the shaft I60 bya clutch which is denoted as a whole at I64. One member of this clutch is formed integral withthe spider I62 and the other member is keyed to theshaft I60., The shaft I60 is connected to thepropeller shaftof the ship by a clutch, one member of which is shown at, I65. Thisclutch member I65 is keyed to the shaft I62.

With the construction shown in Fig. 4, it will be seen that the herringbone gear I45 is journaled on the spiders I51 and I62 by mean of bushings I66 and I61. It will be seen, also, that since the side gears I 49 and I5I are stationary, the planetary units operate as bearings for the ring gear I45, the shaft;I60, and the planetary units themselves, and that, therefore, no radial bearings are required for mounting the shaft I60 or the ring gear I45.

In the embodiment of the invention. shown in Fig. 4, both spiders I51 and I62 are connected to the shaft I60, but if desired, only one of these spiders need be connected thereto, as is thecase in the unit shown in Fig. 3. The other spider can then rotate freely on the shaft. The planetaries provide a 2 to 1 reduction between the shaft I 60 and the ring gear I45. The result is that the size of the gear I45 can be cut in half as compared with the size of herringbone bull. gears required in previousgeared steam turbine drivers; It will be noted, too, that the two planetaries, being mounted directly at opposite... sides of the fbull gear. I45, take,uplitt1e spaceandthat the whole unit isquite compact. It will be seen, therefore, that with the. construction of this invention, it is possible. to;get a much more com-- pact drive than with previous constructions. The smaller size herringbone ears are, of course, much less expensive than thebig" herringbone gears heretofore required and-can'be cut invery much less than half the timerequired for the big gears. v 1 l 2 It is not necessary to employ. bevel gears in the planetary unitsof gear trains" constructed -ac-- cording to the present invention. Spur gear planetariesmay be used insead; 'Insuch-event, as in the case of bevel aplanetariesyoneof :the gears of ,the planetary will be" secured to the driven gear ofthe second reduction, and the other: gear of theplanetarywill be fixed to the gear housing, whilethepinionsof the planetary will be mounted on aspider which is connected to the driven. shaft.. It will be understood, also, thatwhile the-invention has be'endescribed in connection :with .a turbine drive, it-may be applied to otherdrives also. In fact, while several different embodimentspf the invention have been illustrated, the .inventionis capable of further modification, and the present application is intended to cover any adaptations, uses, or embodiments of the invention following, in general, the principles of the invention and including such departures from the present disclosure as come within known or customary practice inthe gear art :and as applied to the essential featuresthereinbefore set :forth k and as fall within the scope of the ninvention Ur -the limits .ofct'he appended @cla ims.

Having thus described any invention, .what I claim is: I

1. In a power drivetwo shafts which are adapted'to be connectedtoa lowpressure and a high pressure turbina' -respectively, a third shaft and a fourth shaft, reduction gearing for driving the third shaft i'from 'th'e shaft which is drivenby the low pressure turbine, reduction gearing "for driving :the fourth shaft from the shaft which is,

driven by theflhigh pressure turbine and at the same speed as the third shaft, :a fifth shaftya gear journaled coaxially thereof "for rotation relative thereto, two 'identieal pinions secured to the :third and fourth shafts, respectively, and meshing with said last named gear at spaced points around its periphery to'drive said last named gear =on rritation-of the third and fourth shafts, and a planetary reduction gearing mounted "coaxially on the fif th shaft for driving the fifth shaft fro'msaid'last named gear, one mem ber of said eplanetarybeing secured to said last named gear, another member of said planetary beingiz'fixed against'rotation, and the p'inions of said planetary being :conneeted 'to said fifth shaft. 7

2. In a power drive, two shafts whichare adapted to be connected to a low'and 'a high pressure turbine, respectively, a third shaft'and a fourth shaft, a set of "bevel-gears for driving the third shaft from the shaft which is driven by the low pressure turbine, a second set if bevelgears for driving the fourth shaft from the shaft which is driven by the-high*pressure-turbine'and at the same speed as the thir'd shaft, :a fifth shaft, a bevel ring gear jeurnaled coaxially thereof and rotatable relative thereto, a bevel'pinion secured to each of the third'an'd fourth shafts and meshing with said bevel ring gear at spaced points around its periphery-tmdrive the bevel'ring gear from theithird and fourth shafts, said bevelpinions vbeing identical, and a set of *bevel planetary gears, which are mounted coaxially of the fifth shaft, :to drive the fifth shaft from said bevel ring gear, said planetary set comprising a pair of bevel :sidesgears, abevel pinion which meshes with both "of said side gears, and 'aspider on which the pinion is retatably mounted, one bevel side gear :of theplanetary being secured to said bevel ring gear, the other bevel side gearof the planetary :be'in'g ifixed against rotation; and the spider of the planetarybeing secured to said fifth,

shaft.

3. Ina :power drive, :a driven gear, -a shaft mounted coaxiall'yiofwthe driven gear but rotatable independentlyithereof, "and two sets of planetary reduction gearing mounted on either side of said driven gear coaxially. of said shaft, one gear of each planetary; set being connected to said driven gear to rotate therewith, another gear of each planetary set. being rigidly fixed against rotation, a :spidersFfor each planetary set mounted ,coaxially :of said shaft, 'the ,pinions of each planetary set-being mounted rotatably on I the spider vof'the set to Emesh with the side gears driven gear torotate therewith the otherb'evel side gearof each setibeing rigidly'fixed against rotationga" rotatable spider for each set, the bevel pinions of each set beingxrotatably mounted on the spider to :mesh'withrtheasi'degears of the set, a shaft mounted 'coaxial-lyioftheitwo spiders and the driven geary'one of @the spiders, at least, being connected to said shaft 'to rotate said shaft on rotation of :the driven gear,:and said driven gear being journaled on the twospiders. 1

5. In a power drive, two shafts which are adapted 'to be connected to a low and a high pressure'turbine, respectively, a third shaft and a fourth shaft, atse't of :beveL gears for driving the third shaft from the shaft which is driven by the low pressure turbine, asecon'd set of bevel gears for driving the fourth shaft from the shaftvvhich is driven by the high pressure -turbine at the same speed as the third shaft, identicalbevel pinions secured tothethird'fand fourth shafts, a bevelrin-g gear with whichsaid last Jna'medpinionsmesh at the spaced "points around its'periphery, two setsof bevel planetary gearing which are mounted at opposite sides er said bevel :ring gear, one of the bevels'ide gears -of each-planetary set being secured to said ring gear "to rotate therewith, the other bevel side gear of eachplanetary set being fixed against rotationga spider for each planetary set, the bevel pinions of each planetary set being rotatably journa'led'onthe spider of the set to mesh with the side gears of the set, said driven gear being journaled on the twdspiders, and'a shaft -to which one of the spiders, at least, is secured, said shaft beingfmounted :coaxially of the driven gear'an'd'of the two sets of planetary gears, V

-6. In a power drive, two shafts which are adapted to be connectedto a low pressureand a high pressure turbine, respectively, a third shaft and a fourth-shaft,reduction gearing for driving the thirdshaft'froimthe shaft which is driven by the low pressure turbine, reduction gearing for :driving the fourth shaft from the shaft which is driven by the high pressure tur-' bine and at thesame speed as the third shaft, a fifth shaft, two identical pinions secured to the third and fourth shafts, a'driven-gear with which the two last namedpinions meshat'spaced points around its periphery, and two sets, of planetary reduction gearing mounted. coaxially of the 'fifth shafteach of 'said two planetary sets comprising two gears, aspider, anda'pinion rotatably mounted on the spider and meshing with both of the gears of the set, one of the'gears of each set being secured to said driven gear and the other gear of reach set :being fixed: against rotation, and the spider-of at least one set being secured to the fifth shaft, said driven gear being journaled onthe-twospidersr; r

- FREDERICK E. MCMULLEN. 

